Michael Anthony Bauer

Issues in Managing Soft QoS Requirements in Distributed Systems Using a Policy-Based Framework

We address the problem of Quality of Service (QoS) requirements for multimedia applications (e.g., distance education, telemedicine, electronic commerce). These applications need to be able to co-exist with more traditional applications for transaction and data processing and have soft real-time requirements. Unlike most other work in QoS management, we provide a framework that does not require users or application developers to have detailed knowledge of the resources needed and resource scheduling and allocation techniques in use. These underlying details are effectively hidden. In this paper, we describe our strategy, an architecture of services to support the strategy and a prototype.

Towards Cloud-Based Analytics-as-a-Service (CLAaaS) for Big Data Analytics in the Cloud

Data Analytics has proven its importance in knowledge discovery and decision support in different data and application domains. Big data analytics poses a serious challenge in terms of the necessary hardware and software resources. The cloud technology today offers a promising solution to this challenge by enabling ubiquitous and scalable provisioning of the computing resources. However, there are further challenges that remain to be addressed such as the availability of the required analytic software for various application domains, estimation and subscription of necessary resources for the analytic job or workflow, management of data in the cloud, and design, verification and execution of analytic workflows. We present a taxonomy for analytic workflow systems to highlight the important features in existing systems. Based on the taxonomy and a study of the existing analytic software and systems, we propose the conceptual architecture of CLoud-based Analytics-as-a-Service (CLAaaS), a big data analytics service provisioning platform, in the cloud. We outline the features that are important for CLAaaS as a service provisioning system such as user and domain specific customization and assistance, collaboration, modular architecture for scalable deployment and Service Level Agreement.

An extended operational profile model

Operational profiles are a quantification of usage patterns for a software application. These profiles are used to measure software reliability by testing the software in a manner that represents actual use. The current definition of an operational profile states that it is the set of operations available in the application, and the operations probabilities of occurrence in customer usage scenarios. This definition is too limited. In most industrial applications, focusing on operations alone does not offer adequate representation of the use of software. The limited definition of operational profiles can restrict their applicability and hence software reliability analysis for many software development organizations. This paper describes a formal and practical extension of the current definition of operational profiles to increase their applicability.

Using the vista 350 telephone to communicate the results of home monitoring of diabetes mellitus to a central database and to provide feedback

PURPOSE Self-monitoring of blood glucose has become routine practice in the management of diabetes mellitus. When all the data is complete, however, the amount of information to be taken into account when making therapeutic decisions becomes overwhelming not only for the patient but for the healthcare provider. Computers excel at processing large amounts of information quickly and impassively, which makes them potentially helpful for collating and communicating the data in a manner that facilitates decision-making by patient and healthcare provider. This should in turn improve control and help prevent acute and chronic complications. METHOD Using the Vista 350 telephone, we have developed a system that enables patients with diabetes to record home monitoring data to a central database and receive feedback summaries. A small trial was conducted to determine if the Vista 350 telephone is an acceptable and feasible method to communicate the results of home monitoring of diabetes mellitus to a central database and receive feedback summaries. A total of 35 volunteers with insulin-requiring diabetes mellitus in the London area were randomly allocated to either use the Vista 350 phone for 6 months, or to a control group that continued to use traditional methods for recording home monitoring data. RESULTS 33 of the 35 patients enrolled completed the trial. All 16 patients who began using the phone continued to do so for 6 months confirming the feasibility of the system. Questionnaires completed at 3 and 6 months confirmed the Vista 350 telephone system to be acceptable to the subjects. The results will enable some minor modifications to be made to the telephone system before a larger definitive trial, designed to determine the effect on diabetes control, is conducted later this year.

Reference architecture for distributed systems management

Management of computing systems is needed to ensure efficient use of resources and provide reliable and timely service to users. Distributed systems are much more difficult to manage because of their size and complexity, and they require a new approach. A reference architecture for distributed systems management is proposed that integrates system monitoring, information management, and system modeling techniques. Three classes of system management—network services and devices, operating system services and resources, and user applications—are defined within this framework, and a detailed hospital application is presented to clarify the requirements for managing applications. It is argued that the performance management of distributed applications must be considered from all three perspectives. Several management prototypes under study within the COnsortium for Research on Distributed Systems (CORDS) are described to illustrate how such an architecture could be realized.

Using policies to drive autonomic management

Required or desired behavior of systems and applications can be expressed in terms of management policies. Such policies can in turn be used to express expected operational characteristics of these systems and possible management actions. We feel that policies can provide the kinds of directives best used for flexible autonomic management systems. The effective use of policies in autonomic management requires that the policies be captured and translated into actions within the autonomic system. In this paper we describe an architecture for an autonomic management and illustrate how policies are defined and mapped into its executable elements and how they are realized as actions. A prototype implementation of the autonomic system for managing an Apache Web server is described and the mechanisms for mapping policies presented

Characteristics of files in NFS environments

As local area networks of workstations and file servers grow, the management of user and system files becomes increasingly more challenging for system administrators. In order to develop effective management tools for these administrators, the nature of files in workstation environments must be understood. This paper presents a static analysis of file usage patterns of a typical workstation environment using a standard client-server paradigm (NFS). The data reveals some differences in characteristics for files in networked environments compared with files in timesharing systems. The study also suggests what data and techniques might be appropriate as a basis for a management tool for network administrators. The paper concludes with a recommendation for the construction of a real-time management and data gathering tool that may give early-warnings of server overload or may be useful in exploring trade-offs among file allocation strategies.

A distributed system architecture for a distributed application environment

Advances in communications technology, development of powerful desktop workstations, and increased user demands for sophisticated applications are rapidly changing computing from a traditional centralized model to a distributed one. The tools and services for supporting the design, development, deployment, and management of applications in such an environment must change as well. This paper is concerned with the architecture and framework of services required to support distributed applications through this evolution to new environments. In particular, the paper outlines our rationale for a peer-to-peer view of distributed systems, presents motivation for our research directions, describes an architecture, and reports on some preliminary experiences with a prototype system.

Supporting dynamic policy change using CORBA system management facilities

Automation of management tasks is an effective counter-measure to the growing complexity of distributed systems. An increasingly popular view redefines the role of the management system to include automated validation and enforcement of policy. This research proposes an architecture for a policy-driven management system which can adapt dynamically to policy change. We show how this architecture can be implemented in a CORBA distributed object computing environment on top of the recently adopted System Management Common Management Facilities.

Towards an improved data centre simulation with DCSim

Computing is increasingly moving into large-scale data centres, providing resources on-demand for clients on a pay-per-usage basis. One form of such on-demand computing is an Infrastructure as a Service (IaaS) Cloud, which provides low level access to virtualized resources. Developing and evaluating data centre management techniques for such large-scale data centres presents a significant challenge. As such, most work turns to simulation tools as the test environment. We present a number of extensions and additional features to an existing simulation tool, DCSim. Our improvements to DCSim include work on the core of the simulator, improved event, communication and management mechanisms, and a more complete model of the structure of a data centre. We also present improved simulation configuration tools and output, including a unique visualization tool. We evaluate the usefulness of the simulator through a demonstration of its use in comparing dynamic VM management techniques.